Apparatus for treating cinematographic films.



P. D. BREWSTER.

APPARATUS FOR TREATING CINEMATOGRAPHIC FILMS.

APPLICATION FILED APR-22,1915.

1,223,664. 7 Patented Apr. 24,1917.

2 SHEETS-SHEET 1.

nunmuu INVENTOR WITNESS s.- r t E BY I mum 1 ATTORNEYJ P. D. BREWSTER.

APPARATUS FOR TREATING CINEMATOGRAPHIC FILMS.

APPLICATlON FILED APR. 22, 1915- V Patented Apr. 24, 1917.

2 SHEETS-SHEET 2- PERCY D. BREWSTER, OF EAST ORANGE, NEW JERSEY.

APPARATUS FOR TREATING CINEMATOGBAPHIC FILMS.

Specification of Letters Patent.

Patented Apr. 24, 1917.

Application filed April 22, 1915. Serial Ho. 28,024.

To all whom it may concern:

Be it known that I, PERCY D. BREWSTER, a citizen of the United States, residing at East Orange, county of Essex, and State of New Jersey, have invented certain new and useful Improvements in Apparatus for Treating Cinematographie Films, of which the following is a full, clear, and exact description.

The present invention relates to the chemical treatment of cinematographic film which is coated on both sides, as, for example, with light-sensitive emulsions, and its chief object is to provide convenient and effective apparatus by which each side can be treated independently of, and without affecting, the other. It is intended primarily for use in color cinematography in which photographic images of the same object are produced on both sides of the film and are then colored or dyed in different colors, as, for example, green on one side and red on the other, but it can be used for other purposes as well. To this and other ends the invention consists in the novel features of construction and combinations of elements hereinafter described. In the accompanying drawings,

Figure 1 shows a convenient and effective form of the invention, in longitudinal section.

Fig. 2 is a plan view of the same.

Fig. 3 is a central cross section.

Fig. 4 is a view showing the preferred form of the invention in longitudinal section, and

Fig. 5 shows a cross section thereof on line 5-5 of Fig. 4.

Referring to Figs. 1, 2 and 3, the tank 1, partly filled with the reagent with which the film 2 is to be treated, is provided in its top with a longitudinal opening or slot 1 along which the film is passed, the width of the slot l being slightly less than the width of the space between the two series of perforations in the film, which mesh with the feed-sprocket 5. The latter is driven by any suitable mechanism, not shown, to draw the film forward at a speed depending, in general, on the rapidity of action of the reagent used, as will be readily understood. Guides of any convenient kind, as for example the metal strips 4, are provided to keep the film in position.

The liquid reagent is drawn from the tank by a pump 6 connected to the outlet 12 by a pipe 7 and is delivered to a longitudinal spray or jet pipe 8 extending under the film inside the tank and having perforations on its upper side by which the liquid is sprayed or jetted against the exposed underside of the film as the latter travels along. Idler rollers 3 may be provided at intervals below the film to prevent sagging thereof too far into the slot, but experience indicates that devices for this purpose will seldom be needed.

The air pressure in the tank is slightly reduced, below that of the surrounding atmosphere, by means of an exhauster 11 connected to the tank by a pipe 13. The effect of the slight vacuum thus produced is to hold the edges of the film snugly down upon the edges of the slot and to maintain a constant stream of air into the tank through any openings into the tank at the edges of the film due to unevenness or irregularity of the film or to perforations therein extending slightly over the edges of the slot, thereby eifectually preventing any liquid thrown against the underside of the film from affectin the upper side.

In Fig. 4 is shown a machine for treating both sides of the film. In this case three receptacles are employed, conveniently provided by dividing the tank 1 transversely into three compartments, 14, 15, 16. The

two end compartments or tanks, 14, 16, may

contain the two different reagents, for example green and red anilin dyes, while the center compartment or tank 15 may contain water for rinsing or washing the feed sprockets, 21, 22, are driven by any convenient mechanism, not shown, and are preferably connected, as by a chain 24. so as to run at the same speed. Between the end tanks the film 2 is looped down into the center tank and is twisted 180, so that the side which was uppermost in passing tank 14 will be the underside in passing tank 16.

The reagents in the tanks 14, 16 can be thrown against the film by the spray or jet method illustrated in Fig. 1, but I prefer to use revolving paddles or brushes 17,- ar- 05 and in contact wi .minute relatively to vided with a pulley 23", Fig. 5, for connection with a suitable driving motor, not shown.

The inlet or low pressure side of the exhauster 11 is connected to the interior of the reagent tanks 14, 16 by branch produce a partial vacuum in sai tanks for the. purpose described. Further insurance against escape of liquid to the upper side of the film is afforded by directing jets of air upon the film and toward the edges thereof, from perforations 20 in a pipe 19 extending along the film at a convenient position above the same. This pipe gets its air from the outlet or high pressure side of the exhauster 11, being connected thereto b a pipe 19. The air jets are intended to blow back to the edges of the film any liquid that in spite of the vacuum in the tank might find its way tothe top of the film.

The apparatus illustrated is intended primarily for dyeing in different colors, the two sides. of a film bearing cinematographic images on both sides, by the well known Traube method or, referably, by bleaching the film on both si es, preferabl by treatment with iodin in a solution 0 potassium iodid, and then dyeing the film, usually red on one side and green on the other. The dyes, in the form of aqueous solutions, in the two end tanks. Where the time of treatment'is the same for both sides of the film the strengths of the dye solutions can be adjusted to give each side its own proper depth of color. For instance, if a een solution acts more slowly than a red so ution of -equal strength the former can be made stronger so as to bring its speed up to that of the other.

The amount of d e carried from the first tank into the was -tank is ordinarily so the amount of water that is used in the latter as to have no appreciable effect on the undyed side of the film even in treating a long length of the latter, it being of course understood that the water is changed frequently enough to revent too reat an accumulation of the ye. If desired, a stream of water can be kept flowing through the wash-tank by providing the latter with an outlet, as 25, and an inlet pipe, as 26, connected with a suitable source of water. I

It is to be understood-that the invention is not limitedto the constructions herein specificall be em 'ed in other forms without departure from its spirit.

I claim:

1. In a film-treating machine, in combination, a tank adapted to contam a reagent and having an opening through which the contents of the tank can reach the fihn, means for passingla film over said opening t the edges thereof whom pipes 18 to are said opening illustrated and described, but can T the side of the film exposed thereto through said 0 'ening, and an exhauster connected with t e tant to produce a partial vacuum therein.

3. In a film-treati nation, a tank' adante and having a film-treating openin in its upper portion, means for passing a over said openin and in contact with the thereof, an means in the tank for b the reagent into contact with the side 0 the film which is exposed through said 0 4. In a film-treating ap aratus, in combination, a tank having a -treat' ing in its upper portion but being 0 erwise closed, means for passi a film over said opening and in contact with the edges there- 0 means for projecting a reagent through and a ainst the exposed side of the film, and air-exhausting means connected with the tank to produce a partial vacuum therein.

5. In a film-treating ap aratus, in combination, a tank havin a -treating opening in its upper portion, means. for p m 1 a 1m over said opening and in contact wi the edges thereof, means for projecting a reagent through said open and against the inner side of the film, aiiid means for discharging jets of air against the outer surface of the film.

6. In a film-treating ap aratus, in combination, a tank having a -treat' opening in its upper portion but being closed, means for passin a film over said opening and in contact with the edges there- 0 means for projecting a reagent through said opening and against the inner side of the film means'for producing a partial vacuum in the tank, and means for discharfing jg; of air against the outer surface 0 the apparatus, in combi- 7. In a film-treating a paratus, in combination, a tank having a m-treating openin its upper portion, means for passin a film over said 0 ening and in contact vi the edges thereo means for pro'ecting a reagent through said ogemng' an against the innerside of the 1m, air-exha apparatus having an inlet connected with the tank to produce a partial vacuum the and means receiving air from an outle t d f to contain a reagent-- open- I for passing means for producing a partial vacuum 1nthe tanks, and means in each of the pair of tanks to project a reagent against the exposed side of the film.

9. In a film-treating apparatus, in combination, a pair of treating tanks each having a film-treating openin in its upper portion, means for passing a lm over the openings in succession and in contact with' the edges thereof, the film being twisted between the tanks whereby one side of the film is exposed to the interior of one tank and the other sideis exposed to the interior of the other tank, a washing tank between the treating tanks, means in each treating tank for projecting a reagent against the exposed side of the film, and means for producing a partial vacuum in the treating tanks.

bination, anelongated tank having a longitudinal slot in its top and being otherwise closed, a film-feeding sprocket to draw a film along the top of the slot with the underside of the film exposed to the interior of the tank, means for projecting a reagent upwardly against the exposed underside of the film, and an exhauster connected with the tank to produce a partial vacuum therein.

11. In a film-treating apparatus, in combination, a pair of treating tanks each having a film-treating opening and each adapted to contain a reagent, means in each tank for bringing the reagent therein into contact with the' exposed side of the film, a washtank between the treating tanks, a sprocket arranged to draw a film over the opening in one treating tank and into the washing tank, a sprocket arranged to draw the film out of the washing tank and over the opening in the other treating tank, and means for driving the sprockets to produce a uniform movement of the film over both said openings.

12. In a film-treating apparatus, in combination, a pair of treating tanks each adapted to contain a reagent and each havmg a film-treating opening for exposing a film to the reagent, means in each tank for bringing the reagent therein into contact with the exposed side of'the film, a washing tank between the treating tanks, and means for passing a film over the opening in one tank, into the washing tank, and over the opening in the other tank, in succession.

13. In a film-treating apparatus, in combination, a tank adapted to contain a reagent and having an opening for exposing a film to the reagent, means for passing a film over said opening with one side of the film exposed to the interior of the tank, means for bringing the reagent into contact with the exposed side of the film, and means operating to prevent access of the reagent to the outer surface of the film.

14%. In a film-treating apparatus, in combination, a tank adapted to contain a reagent and having an opening for exposing a film to the reagent; means for passing a film over said opening with one side of the '10. In a film-treatmg apparatus, in com-- film exposed to the interior of the tank, means for bringing the reagent into contact with the exposed side of the film, and means, comprising an exhauster connected with the tank, operating to prevent access of the reagent to the outer surface of the film.

15. In a film-treating apparatus, in combination, a tank adapted to contain a reagent and having an opening for exposing a film to the reagent, means for passing a film over said opening with one side of the film exposed to the interior of the tank, means for bringing the reagent into contact with the exposed side of the film, and means operating to cause greater air pressure on the outer side of the film than on the inner side, whereby to prevent access of the reagent to the outer surface of the film.

In testimony whereof I hereunto aflix my signature.

PERCY D. BREWSTER. 

